1. Field of the Invention
The present invention generally relates to a portable terminal, and in particular, to an apparatus and method for generating reset signals for function chips in a portable terminal.
2. Description of the Related Art
Along with the recent deployment of various mobile communication services including broadcasting, multimedia video, e-mail, and multimedia messages, the potential of new emerging markets in the mobile communication industry is currently being tested. In this information era, users demand wireless multimedia services with a variety of Quality of Service (QoS) classes ranging from low-rate to high-rate services and from real-time to non-real-time services.
To meet the service demands, portable terminals are under development to support multiple functions. Accordingly, the portable terminals are provided with a plurality of additional function chips. These function chips are operated by power received from a battery under a control of a master chip.
The master chip supplies power to the function chips with their specific functions and controls the function chips to operate at reset timings requested for them, for their stable operations.
That is, the portable terminals are equipped with a plurality of function chips owing to the trend toward multiple functions. This implies that the master chip should generate additional control signals for controlling the function chips.
Conventionally, the master chip provides a reset signal to the function chips using dedicates ports designated for resetting the function chips or for using General Purpose Input Output (GPIO) ports as dedicated ports.
As a result, since the master chip provides the reset signals via a limited number of GPIO ports, there is a shortage of control ports for controlling the function chips corresponding to service functions added to the portable terminals.
FIG. 1 is a block diagram of a conventional reset signal generator.
Referring to FIG. 1, a power management Integrated Circuit (IC) 20 generates a reset indication signal “Reset_IN” a predetermined time after sensing power supplied from a battery 10 and provides the reset indication signal “Reset_IN” to a reset indicator 102.
Upon receiving the reset indication signal Reset_IN at the reset indicator 102, a master chip 100 generates reset signals for controlling a plurality of functions chips 130, 132, 134, and 136, used to achieve multiple functions, and provide the reset signals to the function chips 130, 132, 134, and 136 via dedicated ports. The function chips 130, 132, 134 and 136 include, for example, a Liquid Crystal Display (LCD) chip 130, a camera chip 132, a Bluetooth® (hereinafter, “Bluetooth”) chip 134, and an application chip 136. The master chip 100 uses at least four GPIO ports 112, 114, 116, and 118 as dedicated ports, which are matched to the function chips 130 to 136 in a one-to-one correspondence.
Thus, the master chip 100 provides a reset signal to the LCD chip 130 via the GPIO port 112 (GPIO X1). The GPIO port 114 (GPIO X2) is used as a dedicated port through which a reset signal is provided to activate the camera chip 132. The GPIO port 116 (GPIO X3) is used as a dedicated port through which a reset signal is provided to the Bluetooth chip 134. The GPIO port 118 (GPIO X4) is used as a dedicated port through which a reset signal is provided to the application chip 136.
The master chip 100 also provides a control signal to a memory 150 that stores data for operating the function chips 130, 132, 134, and 136. The master chip 100 includes at least 25 address ports 120 to 128 through which to transmit particular addresses to the memory 150, and data ports (not shown) through which data is allocated to be written/read at the addresses.
Conventionally, as described above, the GPIO ports 112, 114, 116, and 118 are used as dedicated ports for providing the reset signals to the functions chips 130, 132, 134, and 136.
Although the GPIO ports are versatile in their usage according to their operation programs, use of the GPIO ports is limited as dedicated reset ports for providing reset signals.
Moreover, when other function chips are additionally provided to the portable terminal to realize multiple functions, the master chip 100, having the limited number of GPIO ports 112, 114, 116, and 118, cannot generate and provide reset signals for the additional function chips. In other words, the master chip 100 generates and provides the reset signals only for the function chips 130, 132, 134, and 136 connected to the limited number of GPIO ports 112, 114, 116, and 118.
Accordingly, more dedicated ports are needed to provide reset signals to the added function chips in the conventional portable communication system requiring additional functions. However, the allocation of versatile GPIO ports for transferring reset signals that are not frequent, and the allocation is not preferable in implementing a communication system.
Accordingly, there exists a need for a technique for efficiently utilizing ports through which to provide reset signals and a technique for efficiently providing a control signal in relation to the transfer of the reset signals in a portable terminal.